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[An in-vitro evaluation of the Sichuan Union Univ-I membrane lung and mathematical modeling calculation].

A new ELF hollow fibre lung, Sichuan Union Univ-I(SUU-I), constructed in our laboratory was tested in vitro to evaluate its oxygen transfer performance before it undergoes expensive animal trial. The test rig, conditions, procedure and the modelling method are introduced in the present paper. The results demonstrate that the Sichuan Union Univ-I membrane lung possesses the gas exchange ability claimed in the AAMI standards, and approaches the levels of the widely accepted membrane lungs, MAXIMA (Medtronic, US), SARNS(3M, US) and SAFE-II (Polystan, Denmark). The in vitro technique described in this paper proved practical, economical, and simple in the design and manufacturing of a new type membrane lung, as well as in research and development of membrane lungs.

Carbon Dioxide↗

Jenfluor ap--a novel fluorogenic substrate for in situ detection of alkaline phosphatase activity.

Alkaline phosphatase (AP) activity is often targeted in enzyme-related histochemistry as probe enzyme to detect neoplastic cells, as marker for primordial germ cells as well as in preimplantation studies, osteoblast differentiation, phosphate starvation in bacteria, yeast and phytoplankton. Moreover, AP-marker activity is a very useful tool in immunohistochemistry to detect gene sequences, antigens and antibodies. Here we describe a novel high resolution fluorescence method to localize AP-activity in cells and tissue sections based on a naphthol-AS azo coupling procedure (Jenfluor ap). This method provides amorphous photostable fluorescent final reaction products without any diffusion artifacts which are visible in conventional fluorescence microscopes as well as in confocal laser scanning and near infrared multiphoton laser scanning microscopes. The superiority of the Jenfluor ap method in comparison to the known Fast Red TR salt as well as the ELF stains is discussed.

Alkaline Phosphatase↗

[Biological effects of exposure to electromagnetic fields: introduction].

A widespread agreement on the presence, if any, of an association between non deterministic effects and exposure to electromagnetic fields (ELF and RF-MW) has not been reached yet. Some critical points of the pooled analyses of data that lead to the conclusion of the International Agency for Research on Cancer (IARC) are examined. While waiting for more well planned scientific studies, it seems important for scientific experts to give the most sober interpretation of current data, considering the widespread and growing attention of the general population for this subject.

Electromagnetic Fields↗

[The point of view of the Italian Association of Medical Radioprotection: proposal of the Italian C.E.M. Observatory].

Taking in consideration the suggested guide-lines for the health-surveillance on workers exposed to N.I.R. and in particular to ELF and radio-frequency, a work-group of A.I.R.M. suggests the constitution of an italian network for electro-magnetic fields. An observatory will be founded to value the professional exposures and the undue situations of risk, a parallel one will take the census of the workers subdivided into classes for exposure levels, pathologies or symptomatologies imputable to electro-magnetic fields. This suggestion is addressed to the national environmetal hygienists and occupational physicians that are interested.

Electromagnetic Fields↗

[The effect of extremely low frequency magnetic fields on cytochrome oxidase subunit 1 mRNA transcription].

OBJECTIVE: To clone and identify MF-1 gene which responded to extremely low frequency magnetic fields(ELF MF) in Daudi cells, and explore the response universality of MF-1 gene in several MF-sensitive cell lines, so as to provide experimental basis for revealing the mechanism of biological effects induced by magnetic field. METHODS: The DNA fragment of MF-1 was cloned and sequenced; the mRNA level of MF-1 gene were analysed in MF-sensitive cell lines(HL-60, L1210 and CHL) by Northern blot after these cells being treated with 0.1 mT and 0.8 mT MF for 20 minutes and 24 hours, respectively. RESULTS: The MF-1 cDNA sequence had 100% homology with cytochrome oxidase subunit 1 gene(CO1) by searching Gene Bank database; the transcription of CO1 in HL-60, L1210 and CHL cell lines which exposed to 0.1 mT and 0.8 mT MF for 20 minutes were significantly lower(0.38 +/- 0.12 and 0.37 +/- 0.04) than that of control(0.58 +/- 0.12) and so did for 24 hours exposure(0.46 +/- 0.09 and 0.45 +/- 0.09 vs 0.65 +/- 0.06) (P < 0.05). CONCLUSION: CO1 is a MF-responsive gene. Cytochrome oxidase activity may be affected through low level of CO1 transcription by magnetic fields, thus induce bioeffects in organisms.

Animals↗

[Patient with stomach cancer with metastases. What is the value of chemotherapy?].

In comparison with supportive measures alone, chemotherapy in advanced gastric carcinoma is associated with a significant increase in survival and improvement in quality of life. The following substances are considered to be effective and suitable for combination therapy: 5-FU +/- folic acid, cisplatin, irinotecan, etoposide, taxol, and taxotere. In contrast, the effect of doxorubicin and epidoxorubicin is only moderate. Although "second generation" combinations, such as FAMTX, ELF or cisplatin/5-FU, induced higher remission rates as the "first generation" combinations, they failed to improve survival times to any appreciable extent. Currently accepted standard treatment of metastatic gastric carcinoma is infusional 5-FU + cisplatin or ECF. The third generation combinations containing taxane, irinotecan, oxaliplatin appear to be at least equally effective.

Antineoplastic Combined Chemotherapy Protocols↗

[Effects of extremely low frequency electromagnetic fields on the level of c-fos mRNA in brain and liver of mouse].

OBJECTIVE: To study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on c-fos gene expression in mouse brain and liver tissues. METHODS: Mice were exposed to 50 Hz sinusoidal 0.2 mT or 6.0 mT electromagnetic field for 2 weeks or 4 weeks. Competitive RT-PCR method was used to measure c-fos mRNA level. RESULTS: After exposure to 0.2 mT or 6.0 mT field for 2 weeks, c-fos mRNA levels in brain tissue [(0.0178 +/- 0.0076) amol/120 ng cDNA and (0.0092 +/- 0.0042) amol/120 ng cDNA respectively] were higher than that of control level [(0.0012 +/- 0.0005) amol/120 ng cDNA] (P < 0.05). In liver tissue c-fos mRNA levels [(0.0117 +/- 0.0055) amol/120 ng cDNA and (0.0148 +/- 0.0162) amol/120 ng cDNA respectively] were also higher than that of control level [(0.0005 +/- 0.0005) amol/120 ng cDNA] (P < 0.05). After exposure to 0.2 mT or 6.0 mT field for 4 weeks, c-fos mRNA levels in brain tissue [(0.0100 +/- 0.0054) amol/120 ng cDNA and (0.0198 +/- 0.0079) amol/120 ng cDNA respectively] were higher than that of control level [(0.0015 +/- 0.0008) amol/120 ng cDNA] (P < 0.05). In liver tissue the exposure induced much higher expression level [(0.0173 +/- 0.0122) amol/120 ng cDNA and (0.0133 +/- 0.0090) amol/120 ng cDNA respectively] while no expression was found in the control. CONCLUSION: Exposure to 50 Hz electromagnetic fields may induce up-regulation of c-fos transcription in mouse brain and liver tissue.

Animals↗

Smoking-induced changes in epithelial lining fluid volume, cell density and protein.

Bronchoalveolar lavage has proved a useful research technique for recovering cellular and molecular contents of the lower respiratory tract. Because the recovered fluid is variably diluted, an accurate estimation of molecular and cellular concentrations can only be made if the epithelial lining fluid volume recovered is also known. It has been suggested that smoking may alter epithelial lining fluid volume by reducing clearance or by stimulating production and, thus, affect the interpretation of bronchoalveolar lavage studies. In this study, urea was used as an endogenous marker of epithelial lining fluid volume in a comparison of 26 smokers and 31 nonsmokers. The mean epithelial lining fluid volume recovered from smokers was significantly greater than that of nonsmokers (2.4 +/- 1.40 ml vs 1.2 +/- 0.75 ml, p less than 0.005). The total cellular concentration in the bronchoalveolar lavage fluid in smokers was also greater (94.2 +/- 46 x 10(6) vs 33.9 +/- 21.5 x 10(6) cells per 300 ml lavage), even when corrected for bronchoalveolar lavage volume recovered (63.1 +/- 32.5 x 10(6) vs 24.9 +/- 13.3 x 10(6) cells per 100 ml recovered lavage fluid). This was true for macrophage, lymphocyte and neutrophil cell numbers. However, when corrected for the apparent epithelial lining fluid volume, only the macrophage count remained significantly higher in the smokers compared with nonsmokers (30.66 +/- 20.7 x 10(6) vs 18.21 +/- 8.6 x 10(6) macrophages.ml-1 ELF). In addition, concentrations of albumin and immunoglobulin M (IgM) were significantly lower in smokers after correction for epithelial lining fluid volume. These results highlight smoking as a confounding factor in the interpretation of bronchoalveolar lavage data.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoalveolar Lavage Fluid↗

Development of preincubated chicken eggs following exposure to 50 Hz electromagnetic fields with 1.33-7.32 mT flux densities.

The effects of applying extremely low-frequency (50 Hz) electromagnetic fields (ELF-EMF) for 24 hr and different densities (1.33-7.32 mT) were examined on healthy, freshly fertilized white leghorn chicken eggs (55-65 g). Results showed no increase in the rate of abnormalities in exposed groups, but were only significant in 4.19, 5.32 and 5.86, 6.65 mT densities. Alizarin red S and alcian blue 8GX staining showed some embryos with extra ribs, defects in ribs and vertebrae, anuria and abnormal beaks. Study of egg weight, after 9 days of incubation, showed no significant differences between control, sham-exposed and experimental groups. Analysis of crown-rump, beak-occipital length and weight of embryo, showed significant decrease in weight at 4.39 and 5.52 mT intensities, comparing with control and sham-exposed groups. These results revealed that 50 Hz electromagnetic fields can even induce developmental alterations in preincubated chick embryos and confirm that its strength could be a determinant factor for the embryonic response to extremely low frequency EMFs (window effects) prior to incubation.

Animals↗

On the modulation effect of pulsing and static magnetic fields and mechanical vibrations on barley seed hydration.

The changes of wet and dry weights of barley seed in different periods of swelling were studied in seeds treated with Extremely Low Frequency Electromagnetic Fields (ELF EMF), Static Magnetic Fields (SMF) and Mechanical Vibrations (MV) in cold (4 degrees C) and warm (20 degrees C) distilled water as well as in seeds non-treated (control). The metabolic dependent seed hydration, dry weight loss and water binding in seed were modulated by preliminary EMF, SMF and MV-induced treatment of distilled water. The specific electrical conductivity (SEC) of control and treated distilled water was measured before the seed incubation. Frequency and intensity "windows" (i.e. range of frequency or intensity) for the effect of EMF, MV and SMF (correspondingly) on seed hydration, solubility and water binding in seed were studied. These "windows" were different in various phases of seed swelling. It is suggested that water structure modification is the result of valence angle changes (SMF and EMF) and dipole molecules vibration (EMF and MV) has different effects on the process of hydration, solubility and water binding in seed. These results are important from the point of understanding the mechanisms of the biological effect of EMF, as well as from the point of agriculture.

Dehydration↗

[Psychological aspects of perception of magnetophosphenes and electrophosphenes].

Scientific research at the Helmholtz Institute for Biomedical Engineering at Aachen University indicates that ELF (extremely-low frequency) electric and magnetic fields may generate visual perceptions in the human retina which are similar to the pressure phosphenes. During our own experiments we found that 90% of subjects undergoing a blind experiment reported various visual sensations which were mostly colored and moving. Our findings indicate that the psychological component of the perception of electric and magnetic phosphenes must not be underestimated. It is possible that there is a connection between retinal noise in the dark (due to metabolic processes [5, 8]) and magnetic or electric phosphenes.

Adolescent↗

Management of esophageal, gastric, pancreatic, and hepatobiliary neoplasms.

Data published during the latter part of 1980s have shown that the natural history of gastrointestinal cancers can be influenced by treatment. This was further confirmed in esophageal cancers, for which many phase II studies have shown that chemotherapy with and without radiotherapy can induce major responses before surgery. Trials demonstrating a survival benefit are needed. Gastric cancers were confirmed to be sensitive to chemotherapy. Treatment based on combinations of fluorouracil, methotrexate, doxorubicin, etoposide, and cisplatin have shown high response rates (FAMTX [fluorouracil, doxorubicin, and methotrexate], EAP [etoposide, doxorubicin, and cisplatin], ELF [etoposide, leucovorin, and fluorouracil]) and a survival benefit (FAMTX). Adjuvant treatment after surgery using the FAM (fluorouracil, epirubicin, methotrexate) regimen has failed to improve survival. The prognosis for other cancers remains dismal. When all types of gastrointestinal cancers except colon cancers are reviewed, current data indicate that chemotherapy should not be recommended outside the confines of prospective studies.

Adenocarcinoma↗

[Health surveillance guidelines after the European directive on electromagnetic fields].

Directive 2004/40/CE of the European Parliament points out what an occupational physician has to do in case of scientifically evident effects of electromagnetic fields, meaning for evident effects, those one based on the agreement of the scientific community about their causal agents. The Directive, instead doesn't mention physician's tasks in case of possible effects for the exposure to occupational risk. Health surveillance is the estimation of the worker's state of health and it is indispensable to elaborate an evaluation of job-fitness. The clinical test must include the anamnesis, the medical examination and some diagnostic checks (diagnostic laboratory outline), which supply the occupational physician with a complete clinical picture showing any latent pathology or any conditions of individual hypersusceptibility. Anamnestic and clinical data are collected with a standardized system, all the several frequencies of the electromagnetic spectrum are analysed and the diagnostic protocols concerning eyes, skin, and hematopoietic system are established. Also data of periodical medical examinations and "minimum" complementary checks are established: for ELF, radiofrequencies and microwaves a medical examination with a hematological and biochemicals analysis and eye test and electrocardiogram are necessary every two years. Every occupational physician engaged in health surveillance has to keep up with the evolution of the scientific knowledge and he must observe the possible health damages for workers exposed to electromagnetic radiations: this is a deontological responsibility of the occupational physicians to respect the "precautionary principle".

Electromagnetic Fields↗

[The effect of oral N-acetylcysteine on glutathione concentration in bronchoalveolar lavage of patients with fibrosing lung diseases].

Glutathione (GSH) is an important constituent in protecting the cellular elements within the lower respiratory tract against oxydants. We measured GSH in bronchoalveolar lavage fluid (BAL) in twelve patients with lung fibrosis and compared the data to eight healthy controls. GSH in BAL was 0.71 +/- 0.34 mumol/l in patients with lung fibrosis and 0.88 +/- 0.35 mumol/l in the controls (p greater than 0.05). After relating GSH on the volume of the epithelial lining fluid (ELF), determined by the urea method, GSH/ELF was 93 +/- 71 mumol/l in lung fibrosis and significantly different (p less than 0.005) from 387 +/- 240 mumol/l in the controls. In seven patients (four lung fibrosis, one desquamative pneumonitis, two asbestosis) GSH in BAL was determined before and after seven days of medication with 1800 mg N-acetylcysteine/day. We observed a significant increase of GSH in BAL from 0.93 +/- 0.46 to 1.56 +/- 0.92 mumol/l. Our observations confirm that in patients with lung fibrosis the protective ability against oxydants is diminished and that one parameter of the antioxydative capacity (GSH) can be increased in BAL by oral administration of N-acetylcysteine. Further studies are necessary to investigate the clinical and therapeutic implications of our findings.

Acetylcysteine↗

[Occupational exposure to electromagnetic fields of extremely low frequency (with particular regard to power plants) and the health status of workers, based on a literature review].

Recently a number of studies were carried on concerning malignant neoplasms, mainly leukemia, in workers exposed to electromagnetic fields. The studies focused upon power industry workers operating transmission--distribution lines, power stations, transformer stations and distribution substations which work at power--line frequencies. A review of selected literature was prepared concentrating on the methods describing conditions of exposure to e-m ELF fields as well as on the results of epidemiological studies. Also, the results of experiments carried on in Poland based on materials accessible only to a compact group of power industry experts were presented.

Electromagnetic Fields↗

Host proteins that bind to or mimic SV40 large T antigen: using antibodies to look at protein interactions and their significance.

The papovavirus SV40 is able to induce tumours in susceptible hosts and will transform cells in vitro. Its major early protein, large T antigen, is required for viral DNA synthesis, both in vivo and in vitro, and is also responsible for the oncogenic action of the virus. We have made use of an extensive library of anti-T monoclonal antibodies to investigate the cellular effects of T. Large T shares an antigenic determinant with a growth-regulated host protein, p68, which is a member of an expanding super-family of helicases with particular homology to the translation initiation factor elF-4A. We have also studied the binding and interaction of large T with two particular host components: the replicative enzyme DNA polymerase alpha and the proto-oncogene p53. These two proteins bind to similar regions of T and exert similar effects on its antigenic structure. We found that p53 can block the binding of DNA polymerase alpha to T as well as co-existing with DNA polymerase alpha in a trimeric complex with T. This suggests that these interactions may be important in the oncogenic and replicative action of large T.

Antibodies, Monoclonal↗

Immunoregulatory proteins in bronchoalveolar lavage fluid. A comparative analysis of pigeon breeders' disease, sarcoidosis and idiopathic pulmonary fibrosis.

Bronchoalveolar lavage fluid (BALF) cell profiles, interleukins 1 and 2, (IL-1 and IL-2) and soluble interleukin 2 receptor (IL-2R) levels from patients with pigeon breeders' disease (PBD) (n = 24) and asymptomatic pigeon breeders (n = 10) were compared with those from patients with active sarcoidosis (n = 11), inactive sarcoidosis (n = 10), idiopathic pulmonary fibrosis (n = 25) and normal subjects (n = 10). BALF total cells, lymphocytes and OKT4 receptor-bearing lymphocytes/ml were higher in PBD and active sarcoidosis compared with normals (P less than 0.02 all comparisons). In the asymptomatic pigeon breeders bronchoalveolar (BA) lymphocyte numbers/ml were higher than controls (P less than 0.01) producing a subclinical lymphocytic "alveolitis" in 80% of subjects, although compared with symptomatics, % OKT4 (helper) cell numbers were lower (P less than 0.05). OKT4/OKT8 ratios in both groups were normal, whereas in active sarcoidosis ratios were higher (P less than 0.05) but with considerable overlap. Mean levels of IL-1 and IL-2 were raised in the BALF from all groups compared with normals (P less than 0.01 all comparisons), IL-2 being higher in active sarcoidosis and IPF compared with PBD (P less than 0.01). There was no significant difference in detectable BALF soluble IL-2R between patient groups, although its levels correlated positively with IL-1 (22 paired samples from all groups (rs = 0.8, P less than 0.02) and negatively with % and T-lymphocytes/ml in PBD (rs = 0.75, P less than 0.02, rs less than 0.8, P less than 0.01). However, when BALF soluble IL-2R is expressed in terms of T lymphocytes/ml of epithelial lining fluid (ELF), asymptomatic pigeon breeders had significantly higher levels than their symptomatic counterparts (P less than 0.01). It is concluded that percentage lymphocytes [corrected] are similar in both groups of pigeon breeders, although those with PBD had increased numbers of OKT4 (helper) cells. Patients with active sarcoidosis could not be reliably differentiated from those with acute PBD on the basis of BAL cell profiles. Our results suggest that IL-1 leads to soluble IL-2R formation and that continued antigenic stimulation, as with inhaled pigeon allergens, results in a down regulation of BALF IL-2. Excess BALF soluble IL-2R on a cellular basis suggests a mechanism by which some pigeon breeders remain asymptomatic.

Adolescent↗

Non-ionizing electromagnetic radiation and cancer--is there a relationship?

A number of problems become evident when we attempt to assess the data in this review. We must first acknowledge the fact that EM radiation, as opposed to some chemical and physical pollutants which can be seen, tasted, or detected by odor, is in most situations not detected by human senses. This fact alone, however, does not prove or disprove the conjecture that EMR is a potential health hazard. The studies on the effects of EMR on cell systems, animals, and human subjects, report results which promote in some and reject in others the hypothesis that EMR in the ELF and microwave range is carcinogenic. Much of the criticism of the studies on human subjects centers around (1) quantifying exposure to EM Fields; (2) the epidemiologic-statistical methods used to gather, study, and interpret the data; and (3) lack of data studying co-carcinogens. Although there is no convincing evidence that EMR is carcinogenic, the uncertainty, in addition to the ubiquity of EMR, makes study of its possible health effects and its carcinogenic potential an essential part of future medical and epidemiologic research.

Animals↗